There is considerable interest in large camera networks for automatic video analysis in surveillance, training and entertainment in both civilian and military. As the availability of sophisticated hardware increases, the engineering, military, and scientific communities may leverage the capabilities of large camera networks that cover several square kilometers in various applications. For instance, a city may be interested in surveillance during a large event where the attendees significantly outnumber the human security force.
Early attempts at obtaining a global view of targets in a large scale scene have involved cameras with fixed focal length cameras equipped “bug-eye” lenses or mirrors to view the from an overhead position, such as in a stadium. Tracking one or more targets with fixed focal length cameras is difficult to accomplish and produces approximate results at best.
It would be desirable to track targets with variable parameter cameras, such as pan-tilt-zoom (PTZ) cameras. A significant amount of work has been expended in developing algorithms for scheduling PTZ camera resources. Much of this work has been based on master/slave relationships where one PTZ camera is selected as a master camera, and all other PTZ cameras are selected as slaved cameras such as is described in Krahnstoever, N. O., Yu, T., Lim, S. N., Patwardhan, K., Tu, P. H., “Collaborative Real-Time Control of Active Cameras in Large-Scale Surveillance Systems,” Workshop on Multi-camera and Multi-modal Sensor Fusion Algorithms and Applications, 2008, Faisal Z. Qureshi and Demetri Terzopoulos, “Surveillance Camera Scheduling: A Virtual Vision Approach,” Proceedings of the third ACM International Workshop on Video Surveillance & Sensor Networks, 2005, and R. Collins, A. Lipton, H. Fujiyoshi, and T. Kanade, “Algorithms for cooperative multisensor surveillance,” Proceedings of the IEEE, Vol. 89, No. 10, October, 2001, pp. 1456-1477. Movable PTZ cameras have time-varying fields of view, which makes single PTZ camera tracking more challenging than for fixed cameras. Moreover, active coordination of PTZ cameras requires dynamic optimization of camera coverage when the camera coverage is itself a time-varying function. In the case of systems employing PTZ cameras having a single master and a plurality of slaves, if a target that is initially visible to a master becomes visible only to the slave camera and not to the master camera, the master does not know how next to command the slave camera to track the target.
Accordingly, what would be desirable, but has not yet been provided, is a system and method for effective and automatic control of a plurality of PTZ and possibly fixed cameras for tracking one or more targets and to optimize arbitration and selection of the best available camera for tracking the one or more targets at any given time.